Vandalia, IL
Climate overview — based on NOAA 1991-2020 normals from VANDALIA, IL US.
Year-round temperatures (°F)
Climate summary
Vandalia has an annual average temperature of 54.2°F with about 43.7 inches of precipitation per year. The warmest month is July (average high 86.8°F), and the coldest is January (average low 20.7°F). May is typically the wettest month (5.30 in) and February the driest (2.49 in).
Best time to visit Vandalia
Full guide →Climate change signal
All-time records →0 of 366 (0%) of Vandalia's all-time daily heat records have been set since 2015. If records were spread evenly across the station's history, only about 5% would fall in any given decade.
| 1890s | 7 | |
| 1900s | 84 | |
| 1930s | 0 | |
| 1940s | 0 | |
| 1950s | 0 | |
| 1970s | 38 | |
| 1980s | 73 | |
| 1990s | 58 | |
| 2000s | 58 | |
| 2010s | 48 | |
| 2020s | 0 |
Bars: number of all-time daily heat records still standing that were set in each decade.
Monthly averages
| Month | Avg High | Avg Low | Avg Temp | Precipitation | Snow | Rainy days |
|---|---|---|---|---|---|---|
| January | 36.9°F | 20.7°F | 28.8°F | 2.97 in | — | 9 |
| February | 41.9°F | 24.2°F | 33.0°F | 2.49 in | — | 7 |
| March | 52.7°F | 33.2°F | 42.9°F | 3.32 in | — | 10 |
| April | 65.1°F | 43.3°F | 54.2°F | 4.86 in | — | 11 |
| May | 74.9°F | 54.2°F | 64.6°F | 5.30 in | — | 12 |
| June | 83.7°F | 63.2°F | 73.5°F | 4.87 in | — | 10 |
| July | 86.8°F | 66.6°F | 76.7°F | 3.90 in | — | 8 |
| August | 85.9°F | 64.4°F | 75.2°F | 3.24 in | — | 7 |
| September | 79.6°F | 55.8°F | 67.7°F | 3.07 in | — | 7 |
| October | 67.7°F | 44.0°F | 55.8°F | 3.26 in | — | 8 |
| November | 53.7°F | 34.1°F | 43.9°F | 3.76 in | — | 9 |
| December | 41.5°F | 25.6°F | 33.6°F | 2.69 in | — | 8 |
Climate twins of Vandalia
Why these? →The most climatically similar US cities at least 140 miles away (by monthly temperature + precipitation pattern).